Lives of Eminent Zoologists, from Aristotle to Linnus

Page 59 of 79

In the twentieth, the pistil and stamen are united.

XX. Gynandria: stamens united to the pistil; as in orchis.

The plants of all the above classes have flowers furnished with both stamens and pistils; but in the next three the flowers are unisexual.

XXI. Monœcia: Flowers bearing stamens only, and flowers bearing pistils only, occurring on the same plant; as in the oak.

XXII. Diœcia: stameniferous flowers on one, and pistilliferous flowers on another individual of the same species; as in willows.

XXIII. Polygamia: Flowers bearing stamens and pistils, flowers bearing stamens only, and flowers bearing pistils only, all on the same individual, or on different individuals of the same species; as in the ash and pellitory.

The above classes contain all the plants that are Phœnogamous, or have distinctly perceptible organs of reproduction; the next and last class is composed of the cryptogamous, or those of which the flowers either do not exist, or have not been demonstrated.

XXIV. Cryptogamia: Ferns, mosses, lichens, sea-weeds, mushrooms, &c.

The orders or subdivisions of the classes are founded on the number of the pistils in the first thirteen. Thus, in any of these classes, the first[Pg 298] order is Monogynia, or one pistil; the second Digynia, two pistils, &c. But in the fourteenth class, Didynamia, there are only two orders, Gymnospermia and Angiospermia, the former having four naked seeds, the latter having the seeds enclosed in a seed-vessel. In the fifteenth class, Tetradynamia, there are also two orders, Siliculosa, in which the pod is short, and Siliquosa, in which it is long. The orders of Monadelphia, Diadelphia, and Polyadelphia, are formed from the number of the stamina, and bear the names of Hexandria when there are six, Decandria when there are ten, &c. The orders of the nineteenth class, Syngenesia, are six. In the first, Polygamia æqualis, all the flowers (or florets, as they are here called on account of their small size, and because they are viewed as components of a compound flower) have stamens and pistils, and are equally fertile; in the second, Polygamia superflua, the flowers of the centre have stamens and pistils, those of the circumference pistils only, but both kinds produce seeds; in the third, Polygamia frustranea, the flowers of the centre have stamens and a pistil, and are fertile, those of the circumference neutral, or furnished with a pistil, but steril; in the fourth, Polygamia necessaria, the flowers of the centre have stamens and a pistil, but are steril, in consequence of an imperfection in the stigma, those of the circumference have a pistil, and are fertile; in the fifth, Polygamia segregata, all the flowers are perfect, but each has a small calyx, and the whole are contained within a common involucre; and in the last order, Monogamia, the flowers are separated from each other. In Gynandria, the orders are determined by the number of the stamens. In[Pg 299] Monœcia and Diœcia, the characters distinctive of the classes are employed for the orders. Polygamia has three orders, Monœcia, Diœcia, Triœcia; and the last class, Cryptogamia, is divided into four orders, consisting of the Filices or Ferns, the Musci or Mosses, the Algæ, and the Fungi.

The genera are established upon characters derived from all the parts of fructification compared together, according to their number, figure, proportion, and situation; but as this volume was intended to contain all the plants known to the author, the natural characters thus formed could not be employed on account of their length, and he has used the essential character, which is shorter, and consists of those marks that serve to distinguish the genera from each other in the natural orders; while at the head of each class, the genera are synoptically disposed, being defined by their factitious characters, or those by which one is distinguished from another in the artificial order only.

The remarks which we have already made respecting the generic and specific names, apply equally to this department. These last, in the systems of former botanists, were lengthened descriptions, taken from various circumstances, and seldom in any degree distinctive; but Linnæus reduced them to twelve words at most, and derived them from some remarkable difference in the leaves, roots, stems, or other unvarying properties. These short phrases he continued to call the specific name, but they are now properly considered as the specific character; while he invented what he called the trivial name, consisting of a single word added to the generic, and which we now use as the specific.[Pg 300] The number of species mentioned in the Systema Naturæ amounts to upwards of 7800.

We come now to the third and last volume, containing his arrangement of the objects forming the mineral kingdom. This department has received less elucidation from him than the others. In 1736, he first digested a mineralogical system, in which he attempted to found the genera on definite characters; but he seems to have lost sight of the subject until obliged to attend to it when editing the twelfth edition of his work. There he prefixes to his arrangement a brief account of his theory on the origin of fossil bodies in general, and of their several combinations. His views, however, are extremely fanciful, and cannot be said to have produced any beneficial effect on the study of this science. As they have long ago passed into oblivion, it may afford amusement, if not instruction, to present an outline of them.

The earth originated from water, agreeably to the testimony of Moses, Thales, and Seneca! The sea becoming pregnant gradually produced the dry land, from which the dew rose by evaporation, was elevated into clouds, and again descended in showers. No certain indications of a universal deluge have yet been found, but we every where perceive that land has been formed from the sea.

The water of the ocean, being impregnated by the air, produces a twin birth; the saline principle, which is masculine, soluble, acrid, transparent, and crystalline; the earthy, which is feminine, fixed, viscid, opaque, and attractive. It also nourishes the animal and the vegetable beings, which in course of time are reduced to earth.[Pg 301]

The salts, which are sapid, polyhedral, transparent, multiplicative, soluble into infinitely minute particles, although always retaining the same form, and again becoming concrete so as to form larger particles of the same figure, generate various minerals by crystallizing.

Nitrum, which is aërial, by covering over increases sand.

Muria, which is marine, by corroding attracts clay.

Natrum, which is of animal origin, by deliquescing coagulates lime.

Alumen, which is of vegetable origin, by ramifying produces earthy soil.

These are the Fathers of minerals.

The Earths, which are powdery, drying, soluble, fixed, primitive, are generated or reproduced by crystallizing, precipitating, fermenting, or putrefying. From them, by crystallization or attraction, minerals are reformed, and these again are resolved into earths and regenerated.

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